//
// Created by 吴锐 on 2022/3/1.
//

#include "iostream"
#include "string"

using namespace std;

void test01(){
    string str = "hello";

    str.insert(1,"111");

    cout << "str = " << str << endl;

    str.erase(1, 3);

    cout << "str = " << str << endl;
}

int main(){

    return 0;
}